CD34 and pulmonary fibrosis: On the 7th day of the experiment in the lung parenchyma of mice from intact control with partially reversible pulmonary fibrosis, and in mice with partially reversible pulmonary fibrosis, treated by pegHYAL and spiperone administered alone and sequentially, LT-HSCs (Lin-Sca-1+c-kit+CD34-), ST-HSCs (Lin-Sca-1+c-kit+CD34+) and hematopoietic progenitor cells (Lin-Sca-1+c-kit+) were studied (Fig 4).